We have a limited space available for some of our events and need to limit the number of people attending. We do this presently on a first come, first served basis. We have been using eXtCal for this purpose but it does not allow users to edit their own events.

We would like to have an "Add Me" button at the bottom of the event which would allow a person to sign up for it. Once they were added, the button would change to "Remove Me" - which would allow them to drop out. We do this now with the eXtCal module but I really prefer piCal and it's functionality. You can see how we have events set up here:
http://www.wiretheskiesblue.com/guild/modules/extcal/calendar.php
Click on an event in the calendar and it will show you the people who will be attending.

The other problem we have with eXtCal is that it sorts the names of attendees alphabetically. We would like to be able to sort the listing by the date and time they signed up. That way, we will know who signed up and when.

Any chance this could be implemented in a new version or is it possible to create a hack to do it?

Sean